When attaching implants, such as artificial knee, elbow, finger or hip joints, it is required that the implant, such as a joint or a part of a bone, is positioned as accurately as possible onto the adjacent bone. For this, the most accurate possible incisions must be made to the bone structures adjacent to the joint.
EP 07 102 301.4 of the applicant filed on Feb. 13, 2007 discloses a positioning device for aligning or positioning a device at a bone comprising a positioning tool and a positioning element having at least one base holding part, to which at least one device or base can detachably be attached.
EP 1 574 170 B1 of the applicant discloses an adjustable treatment aid for attaching or positioning a tool for treating a bone comprising a first frame which can be fixed to the bone, a second frame for guiding the tool and an adjusting device which allows the first frame to be spatially adjusted relative to the second frame, wherein the adjustable treatment aid includes a reference star which can be detachably attached to the second frame and further comprises a contact interface for contacting the bone which is to be treated to detect the position of the bone by scanning by contact.
US 2006/0235290 A1 discloses a method of using a surgical navigation system for positioning a medical device relative to an anatomical feature, wherein the medical device is navigated relative to the anatomical feature in a first degree of freedom, the medical device is fixed to the anatomical feature in the first degree of freedom and the medical device is subsequently navigated relative to the anatomical feature in a second degree of freedom. An embodiment shows a navigated aiming tube to define the height and axis of the hole for a pin.
US 2005/0149041 A1 discloses a system for positioning a cutting guide for preparation of a bone of a patient during total knee arthroplasty, comprising an adjustor for adjusting the cutting guide at the bone; structures operatively associated with the adjustor for adjusting the position of the cutting guide in at least one degree of rotational freedom and at least one degree of translational freedom; structures for stabilizing the adjustor at the bone; and structures for engaging the cutting guide.
US 2002/0198531 A1 discloses an apparatus for positing the cutting angle of a bone cutting guide comprising first fastening means to fasten said positioning apparatus to a bone such that all of said apparatus and cutting guide fastening means can rotate relative to the fastening axis; second fastening means to fasten said positioning apparatus at a second fastening location onto said bone, different from the first fastening location, such that said apparatus is fixed in a required position within said rotation relative to said first fastening axis; first adjusting means for adjusting the orientation of the cutting angle in rotation relative to a second axis perpendicular to said first fastening axis, wherein said orientation is known as the anterior posterior slope; and second adjusting means to adjust the height of said cutting guide relative to said positioning apparatus along the third axis perpendicular to the two previous axes, wherein said two previous axes are the fastening axis and the second axis.
US 2002/0038085 A1 of the applicant discloses a method for applying an element to a body, wherein the position of the device for preparing or producing a connection between the body and the element is detected relative to the position of the body.
In general, the usage of a fine adjustable cutting jig or block is quite complex and adds several minutes to the surgery time. If the cutting jig would be placed free hand, this would save time but would not be accurate enough to utilize the benefit of navigated surgery.